Novel pregnant model phantoms for measurement of foetal radiation dose in x-ray examinations

Abstract

This study presents a comparison of novel pregnant model phantoms with a handmade phantom in terms of shape and radiation measurement points to determine which model is more suitable for measuring the foetal radiation dose during x-ray examinations. Novel pregnant model phantoms were constructed using an anthropomorphic phantom in combination with two differently-sized custom-made abdomen phantoms simulating pregnancy, which were constructed from a polyurethane resin. The size and shape of the polyurethane resin were designed based on abdominal sizes and shapes collected from the computed tomography examinations at 18 pregnant patients of one hospital. The handmade pregnant model phantom was constructed using an anthropomorphic phantom and a beach ball containing water. Compared with the handmade phantom, there were additional dose measurement points on the novel pregnant model phantoms. Our model phantoms improved upon the handmade phantom in terms of shape and radiation measurement points. We produced pregnant model phantoms that simulated the shapes and sizes of actual patients for the first time.

Evaluation of radiation dose for inferior vena cava filter placement during pregnancy: A comparison of dosimetry and dose calculation software

“…The size of the two phantoms approximately corresponded to the size of a pregnant woman's abdomen in the second or third trimesters of gestation; hereafter, these are referred to as the small and large pregnant phantoms. 23 The custom‐made abdomen phantoms were constructed using polyurethane. The abdominal circumference values of the umbilicus of the small and large pregnant phantoms were 80 and 95 cm, respectively.…”

“…The absorbed radiation doses during IVC‐F placement were measured using RTDs (RD‐1000, TORECK Corporation, Kanagawa, Japan). 12 , 22 , 23 , 33 , 34 , 35 They consisted of sensors (scintillator: Y 2 O 2 S: Eu, Sm) having a cylindrical shape with dimensions φ4.1 × 11.5 mm (Figure 2 ), an optical fiber cable, a photodiode, and a digital display that included the power supply. RTDs for fetal doses were implanted at 6 and 11 points at the umbilical level of the small and large pregnant phantoms, respectively (Figure 3 ).…”

“…In a previous study, 23 the anatomical geometry of the small and large pregnant phantoms in actual measurements were made based on the shape, fetal location, and CT number in actual pregnant patients. Because the shapes of the tube current modulation in the z‐axis for the pregnant model phantom satisfactorily simulated that of a patient, 23 the 6 and 9 month phantoms are similar to the actual pregnant patient. The anatomical geometry of pregnant model phantoms can be used as the phantoms using the dose calculation software.…”

“…Recently, radiation dose in the field of medicine has been lowered through advanced equipment and studies investigating diagnostic reference levels. 13 , 14 , 15 , 16 , 17 , 18 Accordingly, several dose reports 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 have been published for the examination of pregnant women or fetuses using X‐ray imaging. Matsunaga et al.…”

Evaluation of a New Real-Time Dosimeter Sensor for Interventional Radiology Staff

“…Medical radiation (patient radiation doses and occupational exposure) is a major problem in radiation medicine [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ].…”